explaining OCD

what approach is used to explain OCD

biological approach

what two biological explanations are used

genetic explanation

neural explanation

what is a gene

a section of DNA/ sequence of bases inherited from our parents which codes for a protein that results in a physical characteristic e.g. eye colour

what falls under the genetic explanation

-family studies

-candidate genes

outline the researcher and findings for a famous family study + what it suggest about OCD

LEWIS - examined patients with ocd and found

37% had parents with ocd

21% had siblings with ocd

» suggests ocd may be inherited since it runs in families and that the more genetic similarity = higher vulnerability

what are candidate genes

individual genes that increase a persons vulnerability for a disorder e.g. ocd

outline the researcher and findings for a famous study on candidate genes + what it suggests about OCD

TAYLOR found 230 gene variants associated with risk of developing ocd

» ocd is polygenic = influenced by many different genes rather than one single gene

» ocd is aetiologically heterogenous = the origin of the disorder varies from person to person, ocd can arise from different combination of genes

strength and weakness of genetic expl

:) supp research - 68% MZ twins (share 100% same genes) both had ocd whereas 31% DZ twins (share 50% same genes) both had ocd, incr validity to LEWIS study and idea that greater genetic similarity = higher risk of developing ocd, largely influenced by genes and might be inherited

:( biologically reductionist - reduces disorder down to simple biological components and doesn’t consider how env. factors contribute, diathesis stress model more appropriate as it suggests psychological disorders result from the interaction of: diathesis - vulnerability & stress - a trigger, which is holistic approach as it emphasizes how nature & nurture must interact for the disorder to develop, neither alone is sufficient

what falls under the neural explanation

how changes in neurotransmitter levels & brain structures contribute to ocd

what do we know about neurotransmitters in ocd

serotonin - TO LOW

serotonin is linked with mood regulation, low levels disrupt transmission of necessary amount of serotonin leading to low moods

give 3 brain structures involved in ocd, what their responsible for & what its like in an ocd individual

frontal cortex - detects potential threats, initiates alert and controls compulsive behaviours

basal ganglia - filters out unnecessary worry signals received from frontal cortex (ocd = filtering function is impaired so worry signals pass)

thalamus - (ocd = unnecessary worry signals make thalamus hyperactive creating strong signals back to frontal cortex increasing compulsive behaviours)

frontal cortex > basal ganglia > thalamus

strength and weakness of neural expl

:) scientific evidence e.g. use of PET scans has shown ocd patients have more active frontal cortex supports neural explanation of brain structure impairment, objective and standardised methodology

:( serotonin may not be as relevant or even linked to ocd - many ocd individuals also suffer from depression, comorbidity having 2 disorders at the same time, with depression person experiences low levels of serotonin, this is believed to also be the same for ocd but that may not be the case

:( biologically reductionist - reduces disorder down to simple biological components and doesn’t consider how env. factors contribute, diathesis stress model more appropriate as it suggests psychological disorders result from the interaction of: diathesis - vulnerability & stress - a trigger, which is holistic approach as it emphasizes how nature & nurture must interact for the disorder to develop, neither alone is sufficient